High tension interrupter switches



April 19, 1955 A. THIBAUDAT HIGH TENSION INTERRUPTER SWITCHES FiledMarch 26, 1952 I H van 2% A/bew Thzbauam i United States Patent HIGHTENSION INTERRUPTER SWITCHES Albert Thibaudat, Paris, France, assignorto Forges et Ateliers de Constructions Electriques de Jeumont, Paris,France, a corporation of France Application March 26, 1952, Serial No.278,538

Claims priority, application France March 30, 1951 13 Claims. (Cl.200-148) The present invention relates to improvements in high tensioncircuit breakers or interrupter switches of the pneumatic blowout typeactuated by elastic means and having self-contained means for furnishingcompressed air for blowing out the arcs occurring upon opening of thecircuit breaker or switch within its full breaking power range.

Apparatus of this type generally employs cylinders and pistons which areactuated by relatively complex and expensive mechanical systems. Thesesystems involve large inert masses and require considerable force toovercome the inertia. Moreover, they are subject to dilficulties byreason of friction, dead air volumes and head losses, so that theirmechanical and pneumatic efliciency is very low and the availablemechanical energy is poorly utilized. Because of this low efficiency,the opening springs of circuit breakers or switches employing them mustbe very powerful so that the closing of the circuit breaker or switchrequires an undesirably large mechanical force.

It is an object of the present invention to eliminate thesedisadvantages by providing a particularly simple and inexpensiveconstruction. A further object of the invention is to reduce the numberand inertia of the moving parts to a minimum and to eliminatepractically all friction while, at the same time, obtaining highpneumatic efliciency of the blowing means.

In accordance with the invention, the arcing chambers of the circuitbreaker are supported by hollow insulators mounted on a partition whichcarries on its opposite face, directly in line with the hollowinsulators, blowers of the collapsible type which have an air-volumecorresponding to that required for the extinction of full breaking powerarcs are actuated concurrently with the opening of the contacts by meansof frictionless cams which are driven by opening springs, the movingmember of each blower comprising a light pivoted plate or wall which ismechanically joined to the moving contact. In the closed position of theswitch, the moving contact preferably closes the exhaust of the arcingchamber. Upon the opening of the switch, the moving contact leaves thearcing chamber, thereby permitting the air supplied by the blower to bedischarged under pressure.

In comparison with blowers heretofore proposed, those of the presentinvention are distinguished particularly by their special arrangement ofthe air compressing and switch operating means upon a supporting wall,this arrangement making it possible to substantially improve thepneumatic efiiciency of the blow-out action with respect to priorconstructions. The invention is further distinguished by a specialarrangement of the operating mechanism, which is of very simpleconstruction and works with a very high mechanical efficiency, and byother improvements which will be described below. These characteristicsmake it possible greatly to reduce the mechanical forces required foroperation of the circuit breaker and blower and to assure, despite thegreat simplicity of the construction, a reliable and efficient operationof circuit breakers having high interrupting capacity.

Other objects and advantages of the invention will appear from thefollowing description and claims in conjunction with the accompanyingdrawings, in which:

Fig. 1 is a diagrammatic side view, partly in section, showing a blowerembodying the present invention.

Fig. 2 is a similar view showing another embodiment.

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Fig. 3 is a similar, though more complete, view showing a modificationof Fig. 1.

In the embodiment illustrated in Fig. 1, a wall or partition 1 carrieson one side a tubular insulator 2 supporting an arcing or interruptingchamber 3 of any suitable type for pneumatic blowout of the areoccurring on the opening of the switch. The partition 1 is provided withan opening 4 in line with the hollow insulator 2. On the other side ofthe partition 1, and directly over the opening 4, there is provided ablower in the form of a compressible and elastic receptacle 5 having avolume which corresponds to that required for the extinction of fullbreaking power arcs of the interrupter. This receptacle may be sphericalor elongated in shape and, in the latter case, may be provided with aplurality of holes communicating respectively with a correspondingnumber of hollow insulators in order to blow the several poles of apolyphase circuit breaker. It is preferably made of rubber or otherelastomeric material having similar properties and has such wallthickness as to be selfsustaining and to return automatically to theposition shown in Fig. 1 while, at the same time, being readilycompressible or collapsible.

The elastic receptacle 5 is compressed by a light wall or plate 6 whichis pivotally connected to the partition 1 at 6A and carries a roller 7which is engaged by a rotary cam 8 mounted on a rotary drive shaft 9.The roller 7 provides substantially frictionless engagement with thecam. A connecting rod 10 connects the roller 7, and hence the plate 6,to a movable member carrying the roving contact of the circuit breaker.This arrangement may be of any appropriate kind, as, for example,illustrated in Fig. 3. It is preferably such that the air exhaustopening of the interrupting chamber is closed by the moving contact whenthe switch is in closed position.

The shaft 9 and cam 8 are biased in the direction of the arrow by apreviously wound opening spring which is confined by a suitable catchas,for example, shown in Fig. 3when the switch is closed. When the springis released, the cam 8 rotates in a counterclockwise direction, asviewed in Fig. 1, and, by engagement with the roller 7, swings the plate6 toward the partition 1, thereby compressing the elastic receptacle 5and forcing air through the hollow insulator 2 to the chamber 3. Thelinkage between the plate 6 and the moving contact of the interrupter ispreferably such that compression of the receptacle 5 produces apreliminary compression of the air in the receptacle and thereafter theconnection rod 10 produces an opening of the moving contact so that theair is blown out with considerable force. Suitable arrangements of themoving contacts and connecting linkages are shown in Figs. 2 and 3.

It will be seen that, with this arrangement, the path of the air, theamount of dead space, the amount of friction, the number of moving partsand the effects of inertia are all reduced to a bare minimum. It isthereby possible to use a lighter release spring-since less force isrequired to open the switch and blow out the arc-and this in turnfacilitates the closing of the switch as it is easier to overcome theforce of the lighter spring.

In the embodiment shown in Fig. 2, the blower is in the form of acollapsible receptacle comprising a portion of the partition 1,including the opening 4, a metal hood 11 mounted on the partition andhaving the form of a sector of a cylinder and a light plate 12 which ispivotally connected to the partition 1 at 12C and swings inside the hood11 with a slight clearance between the plate and hood. The plate 12carries a roller 7-as in Fig. 1which is engaged by a rotary earn 8actuated by the opening spring, as previously described. As the plate 12swings in a counterclockwise direction from the position shown in Fig.2, it compresses the air enclosed in the receptacle, forcing it throughthe opening 4 and hollow insulator 2. An insulated arm 10B rigidlyconnected to the plate 12, and hence swinging with said plate, isconnected by a link 10C with the movable contact 13 of the circuitbreaker so as to open this contact when the wall 12 is swung toward thepartition 1. The movable contact 13 biased by a closing spring 13A, co-

fixed contact, the external circuit controlled by the cir- 3 cuidt1gareaker being represented by the connections A an To facilitate therapid return of the plate 12 to the position shown in Fig. 2, when theswitch is closed, the plate is preferably provided with a check valve 14which is shown in the form of a hinged flap overlying an opening in theplate 12. This valve has the additional advantage of preventing-duringthe closing of the switchthe suction of ionized gases inside the metalblower which is at ground potential. The tightness of the blower isimproved without increasing friction by wide turned back edges 22A whichare provided on the outer edge and end edges of the moving part 12.Flexible packing 12B or other appropriate sealing means can also beprovided between the pivoted wall 12 and the hood 11, if desired.

The application of the invention to a particular circuit breaker isshown in greater detail in Fig. 3. This figure also illustrates thesimplicity and effectiveness of the construction in accordance with theinvention.

In Fig. 3, the interrupting chamber 313 is shown provided with asuitable blowout nozzle 15. This nozzle cooperates with a moving contact16 which closes the nozzle in closed position of the switch. The movingcontact 16 is carried by an arm 17 which is movably supported by aconducting spring 18 attached to a supporting insulator 19 mounted onthe partition 1. The connections A and B go to the high tension circuitcontrolled by the switch.

A blower A mounted on the partition 1 directly opposite the hollowinsulator 2 which supports the separating chamber 313 is similar to theblower 5 of Fig. l but is modified to include the check valve structure14- of Fig. 2. The elastic blower receptacle 5A is compressible by thepivoted plate 6A which, as in Fig. 1, is swung in a counterclockwisedirection by means of a cam 8 which engages a roller 7 on the plate 6A.The pivoted plate is connected to the arm 17 carrying the moving contact16 by means of a connecting rod 10 which has an insulator 10A since thepart 17 may be at high voltage.

The cam 8 is biased in the direction of the arrow F by a spiral openingspring 20. The cam is held in the closed position of the switch, asshown in Fig. 3, by a control lever 25 which is pivotally supported at26 and carries a catch 21 engaging a detent portion 21A on the cam 8. Alight spring 22 holds the control lever 25 in locking position, as shownin Fig.3.

When the catch 21 is released, for example by hand or by a suitableremote control or an overload relay, the release spring 20 is freed andcauses the cam 8 to turn in the direction of the arrow F, swinging thepivoted plate 6A in a counterclockwise direction to compress the blower5A and-through the link 1dmoving the arm 17 carrying the movable contacttoward the left. After a predetermined preliminary period of compressionof the air, the contact 16 comes out of the nozzle 15 and the resultingarc is blown out by the compressed air. The open position of the contactis indicated by the broken lines 16A. An arm 23, which is integrallyconnected with the plate 6A, swings in the direction of the arrow 1'and, when the switch is open, reaches a position in which it is blockedby a resilient second catch 24 on the control lever 25 so that theswitch is kept in its open position.

In order to re-close the switch, the shaft 9 and cam 8 are turned in aclockwise direction and the release spring 20 is thus wound up. Duringthis movement, the elements 6A, 23, 17 and 16 at first remain immobilebut, when the cam 8 reaches the position illustrated in Fig. 3, thecatch 21, under tension of the spring 22, suddenly engages with thedetent 21A of the cam 8. This engagement results in a slightcounterclockwise movement of the control lever 25, causing the catch 24to be displaced toward the right, thereby freeing the arm 23 so that theswitch is rapidly closed by the action of the closing spring 18 which isbiased to move the parts to closed position. The plate 6A swings in aclockwise direction until it is stopped by an abutment 27. During thismovement of the plate, the check valve 14 opens to admit air to theblower 5A.

It will be seen that, despite its great simplicity, the circuit breakerworks effectively and with high efficiency while, at the same time,embodying several advantageous properties, such as an energetic blowingaction, rapid closing and opening of the circuit breaker, pneumaticabsorption of the movement, small fioor space and visible opening of thecontacts. The invention thus makes it possible to manufacture completelyself-contained pneumatic blowout-type high voltage circuit breakers orinterrupter switches very economically, said switches having remarkableinterrupting capacity and having all the safety properties required inoperation.

It will be understood that the arrangements shown in the drawings andparticularly described can be modified in various ways within the scopeof the invention. The individual features of the several embodiments aremutually interchangeable and the cams shown in the drawings may bereplaced by toggle joints or other mechanical movements which are freefrom friction for all practical purposes.

What I claim and desire to secure by Letters Patent is:

1. In a high tension pneumatic blow-out interrupter switch of the kindhaving an opening spring, a self-generating gas blast structure, amovable contact operative in conjunction therewith, an arcing chamber, atubular insulator carrying said chamber, a partition supporting saidinsulator, a blowing nozzle on said chamber, said nozzle being closed bysaid movable contact in the closed position of the switch, operatingmeans for improving the mechanical and pneumatic efiiciency of theinterrupter to reduce the required power of said spring, said operatingmeans comprising a collapsible blower having an air volume correspondingto that required for the extinction of the full breaking power arcs ofthe interrupter and communicating directly with said insulator andchamber, a plate pivotally mounted on said partition and swingable aboutits pivot to operate said blower, mechanical connections between saidpivoted plate and the movable contact, a roller on said plate, a camengaging said roller to swing the plate about its pivot and biased bysaid spring in a direction to move said plate to operate said blower andto open said interrupter.

2. In a high tension pneumatic blow-out interrupter switch of the kindhaving an opening spring, a selfgenerating gas blast structure, amovable contact operative in conjunction therewith, an arcing chamber, atubular insulator supporting said chamber, a blowing nozzle on saidchamber, said nozzle being closed by said movable contact in the closedposition of the switch, a simplified arrangement for improving themechanical and pneumatic efficiency of the interrupter to reduce therequired power of said spring, comprising a vertical wall having anaperture, the tubular insulator being mounted over said aperture on oneside of the wall, a blower of the collapsible type having an air-volumecorresponding to that required for the extinction of the full breakingpower arcs of the interrupter, said blower being mounted on the oppositeside of the wall and communicating directly with the tubular insulatorthrough said aperture, a plate pivotally mounted on the wall andswingable about its pivot to collapse said blower, mechanicalconnections between said pivoted plate and the movable contact, a rolleron said plate, a rotary cam engaging said roller and biased by saidopening spring for applying a torque to turn said cam in a direction toswing said plate to collapse said blower and to open said switch.

3. In a high tension pneumatic blow-out interrupter switch of the kindhaving an opening spring, a self-generating gas blast structure, anarcing chamber, a tubular insulator carrying said chamber, a wallsupporting said insulator, a blowing nozzle on said chamber and amovable contact operative in conjunction with said gas blast structureand adapted to close said nozzle in the closed position of the switch, asimplified arrangement for improving the mechanical and pneumaticefiiciency of the switch to reduce the required power of said openingspring, comprising a blower of the collapsible type having an airvolumecorresponding to that required for the extinction of the full breakingpower arcs of the switch, and an opening connected directly with saidtubular insulator, a plate pivotally mounted on said wall and swingableabout its pivot to collapse said blower, mechanical connections betweensaid plate and the movable contact, a roller on said plate, said openingspring being biased to turn said cam in a direction to swing said plateto collapse said blower and to operate said movable contact.

4. In a high tension pneumatic blow-out interrupter switch of the kindhaving an opening spring, a self-generating gas blast structure, aninterrupter chamber, a tubular insulator supporting said chamber, ablowing nozzle on said chamber and a movable contact operative inconjunction with said gas blast structure which closes said nozzle inthe closed position of the switch, a simplified arrangement for reducingthe power of said spring, comprising a vertical wall having an aperture,the tubular insulator being mounted over said aperture on one side ofsaid wall, a blower of the collapsible type having an air-volumecorresponding to that required for the extinction of the full breakingpower arcs of the switch, said blower being fixed on the opposite sideof the wall and comprising a portion of said vertical wall includingsaid aperture, a sector-shaped hood mounted on said vertical wall andhaving spaced end walls and a curved outer wall and a plate pivotallymounted on said vertical wall and swingable in said hood with slightclearance between said plate and hood, mechanical connections betweensaid plate and the movable contact, a roller on said plate, a rotary camengaging said roller and biased by said opening spring to turn said camin a direction to swing said plate toward said vertical wall and therebyforce air through said tubular insulator, arcing chamber and nozzle.

5. A high tension interrupter switch according to claim 4, in which saidplate has an opening and a valve flap pivotally mounted on the innerside of said plate to close said opening.

6. A high tension interrupter switch according to claim 4, in which theedges of said plate are turned back to provide portions which lie closeto and approximately parallel to the adjacent portions of said hood.

7. In a high tension interrupter switch of the kind having an openingspring, a self-generating gas blast structure, an arcing chamber, atubular insulator supporting said chamber, a wall supporting saidinsulator, a blowing nozzle in said chamber and a movable contactoperative in conjunction with said gas blast structure and adapted toclose said nozzle in the closed position of the switch, operating meansfor improving the mechanical and pneumatic efficiency of the switchcomprising a movable arm carrying said contact, a conducting springmounted on the support and carrying said movable arm, said springtending to close the switch, a collapsible blower having an air-volumecorresponding to that required for the extinction of the full breakingpower arcs of the switch, said blower being directly connected with saidtubular insulator and comprising a plate pivotally mounted on said wall,an insulating link between said plate and the movable arm carrying saidmovable contact of the switch, a roller on said plate, a rotary camengaging said roller, said opening spring being attached to said cam andapplying a torque to the cam in a direction to swing said plate tocollapse said blower and open the switch, a pivoted tripping leverhaving a catch for releasably holding said cam normally in the closedposition of the switch, and a second catch for releasably holding saidpivoted plate in the open position of the switch.

8. In a high tension circuit breaker of the air blast type having anopening spring, a self generating gas blast structure, movable contactsoperative in conjunction with said structure, and are suppressionchambers supported by hollow insulators mounted on a partition, simpleand highly efficient means for blowing out the arcs and operating saidcontacts comprising collapsible blowers having an air-volumecorresponding to that required for the extinction of the full breakingpower arcs of the circuit breaker, said blower being directly mounted onthe side of said partition opposite said insulators and connecteddirectly with said insulators, a light weight wall pivotally mounted onthe same side of the partition as the blowers and swingable about itspivot to operate the blowers, a roller on said wall, a cam cooperatingwith said roller to swing said wall about its pivot to operate theblowers, mechanical connections between said light wall and the movablecontacts of the circuit breaker, said circuit breaker opening springbeing connected to said cam and biased to move said cam in a directionto swing said light wall to open the circuit breaker and operate theblowers.

9. In a high tension pneumatic blow-out circuit breaker of the kindhaving an opening spring, a self-generating gas blast structure, aresuppression chambers, hollow insulators supporting .said chambers, apartition carrying said insulators and movable contacts closing theexhaust of said chambers in the closed position of the circuitbreaker,-means for reducing the power of said spring comprisingcollapsible blowers having an air-volume corresponding to that requiredfor the extinction of the full breaking power arcs of the circuitbreaker, said blower being mounted on the side of the partition oppositethe said tubular insulators and connected directly with said tubularinsulators, a light weight wall pivotally mounted on the same side ofthe partition as the blowers and swingable about its pivot to operatethe blowers, a roller on said wall, mechanical connections between saidwall and the movable contacts of the circuit breaker, trip means forreleasably holding said spring in the closed position of the circuitbreaker, and a cam movable by said opening spring and cooperating withsaid roller to swing said wall about its pivot in a direction to oper-1ate tge blowers and the contacts when said spring is reease 10. In apneumatic blow-out type high tension circuit breaker having an openingspring, a self-generating gas blast structure, are suppression chambers,hollow insulators supporting said chambers, a partition on which saidinsulators are mounted, a spring for opening the circuit breaker andmovable contacts which close the exhaust of said chambers in the closedposition of the circuit breaker, means for improving the mechanical andpneumatic efficiency of said breaker and reducing the power of saidopening spring, comprising collapsible blowers having an air-volumecorresponding to that required for the extinction of the full breakingpower arcs, said blowers being connected with the inlet of said hollowinsulators and disposed on the opposite side of the partition, a lightwall pivotally mounted on the same side of said partition as the blowersand swingable about its pivot to operate the blowers, a roller on saidwall, a cam movable by said spring and acting upon said roller on saidpivoted wall to swing said wall in a direction to operate the blowers,means for releasably blocking said cam in the closed position of thecircuit breaker, and means for mechanically connecting said pivoted walland the movable contacts.

11. A high tension circuit breaker according to claim 10, in which theblowers comprise compressible elastic receptacles.

12. A high tension circuit breaker according to claim 10, in which eachof said blowers comprises a portion of said partition, a metal hood onsaid partition and said pivoted plate, said plate being formed with widebent-over edges which have close clearance relative to said hood.

13. In a pneumatic blow-out type high tension circuit breaker having anopening spring, a self-generating gas blast structure, are suppressionchambers, hollow insulators supporting said chambers, a partition onwhich said insulators are mounted, movable contacts which close saidchambers in the closed position of the circuit breaker, and conductingsprings supporting said movable contacts and biased to close the circuitbreaker, improved means for opening the circuit breaker and concurrentlysupplymg air blasts to extinguish full breaking power arcs occurring onthe opening of the circuit breaker, comprising collapsible blowershaving an air-volume corresponding to that required for the extinctionof said arcs, said blowers being connected with said hollow insulatorsand mounted on the opposite side of the partition, a light wallpivotally mounted on the opposite side of said partition as the blowersand swingable about its pivot to operate the blowers, mechanicalconnections between said wall and said movable contacts to provideconcurrent operation of the blowers and opening of the contacts, and acam movable by said spring to swing said wall to operate the blowers andto open said circuit breaker, a latch for releasably holding said cam inclosed position of the circuit breaker, and a catch for releasablyholding said movable contacts in open position.

References Cited in the tile of this patent UNITED STATES PATENTS1,414,913 Whittingham May 2, 1922 2,055,312 Ruppel Sept. 22, 19362,303,730 Fernier Dec. 1, 1942 2,430,008 Fernier Nov. 4, 1947 2,552,427Heidmann May 8, 1951

